The invention relates to a hopper door opening control apparatus and method for controlling a hopper discharge control member on a railroad ballast car.
Railroad ballast has traditionally been discharged and/or spread by specially designed hopper cars called "ballast cars". In such cars, the ballast is discharged through hopper doors positioned beneath the hopper. When such doors are positioned directly beneath the car, ballast discharged therefrom must be spread by hand, a labor intensive task, or by an additional specially equipped railroad car.
These problems were addressed in U.S. Pat. No. 3,654,872 ('872 patent) in which a ballast car has four hoppers, each of which is provided with a bottom-mounted discharge opening with a discharge control member inserted therein. The discharge openings are centered over a rail and each discharge control member is a pivotable structure with a pair of side walls extending at an angle outward from an arcuate top surface. A bottom wall connects the side walls and a pair of end walls extend past the side walls to form channels on either side of the discharge control member. The discharge control member is attached at a pivot point positioned below the discharge opening. The arcuate top surface covers the discharge opening when the discharge control member is pivoted to a center position. When the discharge control member is pivoted to one side or the other, the discharge opening is partially opened and ballast is released through the channel formed by one of the angled side walls and the end walls and is thus directed to an associated side of the railroad rail. By selectively pivoting the discharge control member, a proper amount of ballast is directed to a desired position which minimizes or eliminates subsequent spreading requirements. On ballast cars containing pairs of side-by-side hoppers, ballast can be selectively distributed inside or outside of each rail to further minimize spreading requirements.
While representing a significant improvement over prior ballast hopper cars, the hopper car door discharge control member in the '872 patent is controlled by a hand-operated lever. Thus, the control opening or openings on each ballast car must be set by hand when the train is stationary and can not be adjusted once the train is in motion.
It is clear that a need exists for an improved ballast car hopper door control apparatus and method which is power driven and which is remotely controllable to allow adjustment while a train including the ballast car is in motion. Such an apparatus and method should also provide for the selective adjustment of any one ballast car in a train carrying multiple ballast cars and of multiple hoppers on a single ballast car.